1. Field of the Invention
The present invention resides in a three directional horizontal drilling process which is suitable for the installation of horizontal wells for in-situ treatment or extraction of undesirable contaminants, for example, fluids and gases, from subsurface formations. Preferably a first extraction well is used in conjunction with a second injection well to expedite the extraction of undesirable contaminants.
Contaminated subsurface formations located under structures such as buildings, storage tanks, roadways, shallow waterways, land farms, and the like, present an especially difficult dilemma which often times are inaccessible by conventional methods in addition to being an expensive problem to correct. The present invention eliminates or solves this problem by utilizing drilling machinery equipped with a steerable drill which can be precisely directed into the vicinity of contaminated formations.
The most common environmental problem encountered in subsurface formations is contaminated ground water. One method of removing contaminants from subsurface formations is by excavating the contaminated subsurface material. This method of eliminating contaminants from subsurface formations is very expensive and time consuming.
Other methods have been proposed for eliminating contaminants from subsurface formations using various vertical well systems for the purpose of extracting said contaminants. Vertical wells, however, suffer from the disadvantage of not being able to exploit fully, because of accessibility on limited subsurface exposure, extraction of contaminants from a subsurface formation because of the vertical configuration of said well systems.
2. Description of the Prior Art
Processes for the extraction of subsurface formations are known and are currently practiced commercially.
For example, U.S. Pat. No. 4,832,122 discloses a system for removing volatile contaminants from a subsurface plume of contamination which utilizes two sets of wells. One well is for injecting a fluid into a saturated zone on one side of the plume and the other well is for extracting and collecting the fluid and volatile contaminants from the other side of the plume.
U.S. Pat. Nos. 4,593,760 and 4,660,639 relate to a method for removing volatile contaminants from the upper, unsaturated zone of groundwater. Vertical wells are sunk into the contaminated zone having casings consisting of two sections. The casings consist of an upper unperforated section and a lower perforated section. Volatile contaminants are extracted through the perforated section of the casing and pumped past the unperforated section of casing to the surface for treatment.
It should be noted that, the prior art of record fail to teach or disclose a three directional horizontal drilling process which is precisely directed into a contaminated subsurface formation to extract contaminants therefrom.